Candles have been known and used for illumination since early civilization. The earliest candles are thought to have been developed by the Egyptians who soaked the pithy cores of reeds in molten tallow and to make rushlights or torches. The Romans are credited with developing the first candle which utilized a wick. The Romans also used tallow, derived from cattle or sheep suet, for candle wax. Around the middle ages beeswax was found to be suitable in candles. Beeswax candles were desirable over other candles because beeswax does not produce a smoky flame, or emit unpleasant odor when burned. Then, as now, beeswax candles were expensive, and prohibitively so, preventing most people from enjoying their advantages. Candles produced from molds first appeared in 15th century France.
In the American Northwest, Native Americans produced light by inserting oily candlefish (dried smelt) into the Y of a slit stick and lighting it. In a similar vein, the Stormy Petrel, and other birds having high fat content, were inserted with a wick and lit like candles.
America's first contribution to candlemaking occurred in colonial times when it was discovered that the grayish-green berries of bayberry bushes could be boiled to produce a sweet-smelling wax that burned cleanly. Unfortunately, extracting wax from bayberries is extremely tedious and the popularity of candles made from bayberry wax soon diminished. Candlemaking next benefited from the growth of the whaling industry because spermaceti, a wax obtained from the head of a sperm whale by crystallizing the whale oil, became widely available. Spermaceti, like beeswax, burned without an acrid odor and was also found to be harder than either beeswax or tallow. This was advantageous because spermaceti did not soften or bend in the heat of summer.
The Industrial Revolution next shaped the production of candles by providing machines which produced candles and paraffin wax, which is produced by refining oil and coal shales. Paraffin, a bluish-white wax, burned cleanly with no unpleasant odor and was more economical to produce than any previous candle fuel. Paraffin did have one drawback, a low melting point, which may have been a threat to its commercial viability if not for the introduction of stearic acid, a by-product of animal fat, into candles.
After the light bulb was introduced in the late nineteenth century the need for candles diminished. A renewed popularity for candles emerged, especially for holidays and religious ceremonies, in the first half of the twentieth century. Much of this growth can be attributed to the growth of petrochemical refining and commercial meat production, which produce the two main constituents of present day candles—paraffin and stearic acid.
Recently environmental, health and supply concerns have sprung up concerning the use of petroleum byproducts in candles. Candle wax formulations based upon natural materials, and in particular vegetable oils, have thus been proposed. However, the production of candles from these waxes has suffered several drawbacks, including cracking, air pocket formation, product shrinkage and a natural product odor associated with vegetable materials. Various soybean-based waxes have been reported to suffer performance problems relating to optimum flame size, effective wax and wick performance matching for an even burn, maximum burning time, failure to achieve a consistent appearance upon resolidification after melting, product color integration and/or product shelf life.
Additionally, there are several types of candles, including taper, votive, pillar, container candles and the like, each of which places its own unique requirements on the wax used in the candle. For example, container candles, where the wax and wick are held in a container, typically glass, metal or the like, require lower melting points, specific burning characteristics such as wider melt pools, and should desirably adhere to the container walls. The melted wax should preferably retain a consistent appearance upon resolidification.
In order to achieve the aesthetic and functional product surface and quality sought by consumers of candles, it would be advantageous to develop new waxes based on vegetable oil that overcome as many of these deficiencies as possible. Utilizing vegetable oil-based waxes would also provide an additional outlet for agricultural production and has the potential for reducing the cost of candle waxes due to a ready supply of raw materials. Accordingly, it would be advantageous to have vegetable based wax materials which can be used to form clean burning base materials for forming candles. The candle base materials should preferably have physical characteristics, e.g., in terms of melting point, hardness and/or malleability, that permit the material to be readily formed into container candles having a pleasing appearance and/or feel to the touch, as well as having desirable olfactory properties.